cracker

(noun) a thin crisp wafer made of flour and water with or without leavening and shortening; unsweetened or semisweet.

(noun) a poor White person in the southern United States. Synonyms: redneck.

(noun) a programmer who cracks (gains unauthorized access to) computers, typically to do malicious things. Examples: "Crackers are often mistakenly called hackers."

(noun) firework consisting of a small explosive charge and fuse in a heavy paper casing. Synonyms: firecracker, banger.

(noun) a party favor consisting of a paper roll (usually containing candy or a small favor) that pops when pulled at both ends. Synonyms: snapper, cracker bonbon.